There are two main ways to control systems that generate power by rotating turbines by using vapour energy. The first one is a method of controlling an operating turbine by using a turbine velocity of the operating turbine, and by controlling active power and reactive power that are generated by the turbine.
The second one is a method of controlling systems used in case of a device malfunction detected due to an abnormality of a temperature and a pressure, and a flow rate of a working fluid at an inlet part of the turbine.
The first control method is generally performed by using a speed governor and a synchronizer. However, the second control method stays at a primitive stage of stopping a cycle by blocking a valve at the time of occurrence of the problem.
Of course, although data such as temperature, pressure, flow rate and vibration is measured in real time while the system is monitored to quickly respond to problems such as device malfunction, a quick post-countermeasure may be available by monitoring the system in real time, but a proactive countermeasure is difficult.
FIG. 1 shows a configuration block of a conventional turbine power generation system.
Device malfunctions due to a temperature, pressure, flow rate, vibration, etc. of an inlet part of a turbine frequently occur due to malfunctions of the turbine that has the most complicated structure. Accordingly, the turbine has to be stopped to diagnose devices.
Referring to FIG. 1, when a device malfunction occurs, conventionally, first the turbine is stopped, and the stopping of the turbine leads to stopping of a boiler and the rest of the devices. However, when a turbine power generating system is re-operated after solving the device malfunction, various problems arise.
For example, condensate water may be generated in an inlet valve of the inlet part of the turbine or in a proportional control valve, thus a turbine blade may be damaged. In addition, non-productive time is spent, and power consumption to reheat the boiler is required.
Heating up to the boiler the normal operating temperature, consumes much energy, particularly as it gets closer to the normal operating temperature.
In addition, when wasted heat of an incineration plant is used for generating power, and a boiler should be stopped due to a device malfunction, an incinerator of the incineration plant itself should be also stopped.
Herein, a bypass pipe that is branched between a heater and a turbine may be installed to bypass a working fluid to a steam condenser so that only the turbine is stopped and other devices are operated.
However, when the bypass pipe is installed, and the working fluid flowing inside the heater that is heated by the boiler's heat by passing the bypass pipe directly flows to the steam condenser, the steam condenser may exceed its condensation volume, and thus malfunctions of the steam condenser and other devices sequentially connected to the steam condenser such as compression pump, etc. may occur.
Accordingly, a means for preventing problems caused by excess heat and recycling the excess heat while other devices except for the turbine being operating is required.
A conventional technique related thereto is described in detail in Korean Patent No. 10-1090534 (Registration date: Nov. 30, 2011) with the tile ‘Automatic power control apparatus for power generator’ that is shown in FIG. 2.
Referring to FIG. 2, the conventional technique discloses an automatic power control apparatus for a power generator that includes a power generator protecting relay 40, a governor 20, and an automatic voltage controller 30, and a PLC central controller 10. The PLC central controller 10 calculates a control value by using operation data received from the power generator protecting relay 40 and a predetermined reference value, and by performing proportional-integral-derivative (PID) operations. The automatic power control apparatus for the power generator further includes a PID logic control program module that controls the automatic voltage adjustor and the governor 20 according to the calculated control value.
According to the above conventional technique, malfunctions of the power generator may be prevented by using an integrated automated control technique rather than a conventional independent manual control technique. In addition, there is an effect of preventing a risk such as a sudden load on an engine. In addition, an engine power generator may be conveniently and safely monitored and controlled by remotely inputting outputs and power factors of respective power generators.
As another conventional technique, Korean Patent No. 10-0848285 (Registration date: Jul. 25, 2008) with the tile ‘Method of providing predictive maintenance with fault diagnostic for power generator control system, apparatus and system therefor’ is shown in FIG. 3.
The above conventional technique discloses a method of providing a predictive maintenance with a fault diagnostic for a power generator control system, and an apparatus and a system therefor. In detail, the method of providing the predictive maintenance with the fault diagnostic for the power generator control system, the apparatus and the system therefor disclose that when a number of fail codes occurs between an exciter of a power generator control system and a turbine control system, a power generator failure diagnosing server detects the failure and stores each fail code in a database, extracts and outputs causes of the respective fail codes and maintenance methods therefor, checks whether or not there is a failure prediction part in the power generator, and outputs the failure prediction part when there is.
As another conventional technique, Korean Patent Application Publication No. 10-2014-0109124 with the title ‘Apparatus for controlling of electric governor in vessel’ is shown in FIG. 4.
The above conventional technique discloses an apparatus for controlling of an electric governor in a vessel, which includes: a local control panel that supplies battery power as governor control power and engine control power through main power, emergency power, or an uninterruptible power supplier; and a governor control panel that controls an engine RPM by controlling a governor actuator of the engine control panel by using governor power supplied from the local control panel, and stops the governor actuator by using the governor control power that is temporally maintained when a failure of the governor power occurs.
As another conventional technique, Korean Patent No. 10-1157294 (Registration date: Jun. 11, 2012) with the title ‘Electric governor controller’ is shown in FIG. 5.
In the above conventional technique, a governor controller includes an emergency operation means and controls an engine operation so that predetermined output power is generated in a situation where urgent power generation is required. Accordingly, it is possible to prevent accidents and inconveniences that may occur due to the inability to operate the engine despite the situation requiring urgent power generation. In addition, it is possible to diagnose when device malfunctions occur, and inform a user of the malfunctions. Thus the user can easily manage operational failures that may occur in the devices.
However, as described above, when the above conventional techniques are applied to turbine power generation systems, there is no means for solving a thermal load that is applied to a steam condenser when only operations of the turbine is stopped.